Plug for fluid pipe connector

ABSTRACT

There is provided a plug  13  for a fluid pipe connector  11  for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank or a processing unit. The plug  13  for fluid pipe connector comprises: a plug portion  61;  a fixed plate portion  87  which is formed on a fluid pipe  60 ; a fixing portion  78  for sandwiching the fixed plate portion  87  between the fixing portion  78  and the end portion of the plug portion  61  to fix and support the fixed plate portion  87;  a cylindrical supporting portion  80  which is integrally provided on the fixing portion  78  for gently supporting thereon the fluid pipe  60;  and a fixing nut for covering and fixing the plug portion  61  and the fixing portion  78.  Between the fixing portion  78  and the cylindrical supporting portion  80,  the engaged surface  79  for a lock lever  52  is provided. On the tip end of the plug portion  61,  a valve  62  is provided for pushing a valve  20  of a member, which is to be connected to the plug  13,  to establish a fluid communication. On the outer peripheral surface of the fixing nut  64,  a long groove  83  is provided for preventing the plug  13  from being erroneously mounted. Thus, it is possible to reduce the size and weight of the plug for fluid pipe connector, and it is possible to improve safety.

BACKGROUND OF THE INVENTION

[0001] 1 Field of The Invention

[0002] The present invention relates to a plug for fluid pipe connector, which is used for a fluid pipe connector for connecting fluid piles to each other or for connecting a fluid pipe to a storage tank, a processing unit or the like.

[0003] 2 Description of The Prior Art

[0004] As a fluid pipe connector for connecting a fluid pipe for allowing chemicals or the like to flow, to a storage tank for storing therein the chemicals, a processing unit or the like, a fluid pipe connector having a flange structure is generally known. As shown in FIG. 2, such a fluid pipe connector 1 comprises one side connecting portion 3 which is provided on an end portion of a fluid pipe 2 on the side of a storage tank, and the other side connecting portion 5 which is provided on a plug body 4. The one side connecting portion 3 and the other side connecting portion 5 are provided with fixing flanges 6 and 7, respectively. The fixing flanges 6 and 7 are fixed to each other by means of bolts 8, so that the fluid pipe 2 is connected to the plug body 4.

[0005] In order to allow chemicals or the like to safely flow, the fluid pipe 2 comprises an inner tube, an intermediate tube and an outer tube, and has a sufficient thickness. In addition, the outer tube is formed of a net material of stainless steel. For that reason, the fluid pipe 2 has a considerably heavy weight.

[0006] By the way, in the fluid pipe connector 1 with the above described construction, the fixing flanges 6 and 7 are clamped by the bolts 8 to connect the one side connecting portion 3 to the other side connecting portion 5. However, since the fluid pipe 2 is heavy, the connection of the one side connecting portion 3 to the other side connecting portion 5 may be loosen. That is, there is a problem in that the weight of the fluid pipe 2 may apply force in a direction, in which the upper sides of the fixing flanges 6 and 7 leave each other, to loosen the connection of the one side connecting portion 3 to the other side connecting portion 5, so that sufficient care must be given.

SUMMARY OF THE INVENTION

[0007] It is therefore an object of the present invention to eliminate the aforementioned problems and to provide a plug for fluid pipe connector, which is capable of supporting thereon a heavy fluid pipe to surely connect the fluid pipe to another fluid pipe, a storage tank, a processing unit or the like.

[0008] In order to accomplish the aforementioned and other objects, according to one aspect of the present invention, there is provided a plug for fluid pipe connector for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank or a processing unit, the plug for fluid pipe connector comprising: a plug portion, the rear portion of which is fixed and from the front portion of which a liquid spouts out; a fixed plate portion which is formed by enlarging the end portion of a fluid pipe outwardly in circumferential directions in the form of a flange shape; a fixing portion for sandwiching the fixed plate portion between the fixing portion and an end portion of the plug portion to fix and support the fixed plate portion; a cylindrical supporting portion which is integrally provided on the fixing portion for gently supporting thereon the fluid pipe; and a fixing nut for covering and fixing the plug portion and the fixing portion.

[0009] With this construction, since the plug portion and the fixing portion are fixed so as to be covered with the fixing nut, the plug for fluid pipe connector can be miniaturized and easily handled. In addition, since the fluid pipe is gently supported on the cylindrical supporting portion, the fluid pipe does not bend at an acute angle. Moreover, the fluid pipe is supported on the cylindrical supporting portion to prevent the fluid pipe from greatly bending at the portion of the fixed plate portion which is sandwiched between the plug portion and the fixing portion to be fixed, so that it is possible to surely prevent this portion from bending.

[0010] The plug for fluid pipe connector is preferably provided with a portion having a difference in level in the outer periphery thereof to provide an engaged surface for a locking mechanism.

[0011] With this construction, the locking mechanism can be engaged with the engaged surface of the outer periphery of the plug for fluid pipe connector, so that it is possible to surely fix the plug for fluid pipe connector.

[0012] The plug for liquid pipe connector preferably further comprises a valve provided on the tip end of the plug portion, the valve being establishing a fluid communication when the valve is pushed into a member, which is to be fixed, to be open.

[0013] With this construction, the plug portion is not open unless the valve contacts and pushes the member which is to be connected thereto. Thus, safety in handling is improved.

[0014] The plug for fluid pipe connector preferably further comprises a long groove for preventing the plug from being erroneously mounted, the long groove being formed in the outer peripheral surface of the fixing nut.

[0015] With this construction, the plug for fluid pipe connector can not be inserted into the member, which is to be connected thereto, unless the long groove is aligned with the member which is to be connected thereto. Therefore, this plug for fluid pipe connector is not erroneously mounted.

[0016] An enlarged diameter portion to be engaged with the fixing nut is preferably formed on the base end of the plug portion.

[0017] With this construction, the fixing nut is engaged with the enlarged diameter portion of the base end portion of the plug portion to fix the plug portion.

[0018] An O-ring for sealing a fluid passage is preferably provided on an end face of the enlarged diameter portion.

[0019] With this construction, the fluid passage is surely sealed by the O-ring when the plug is fixed.

[0020] The plug for fluid pipe connector preferably further comprise a locking nut which pressingly contacts the fixing nut for preventing the fixing nut from being rotated to be loosened.

[0021] With this construction, the locking nut surely prevents the loosening of the fixing nut.

[0022] An annular groove, which is fitted into a locking mechanism to be fixed, is preferably formed in the outer periphery of the central portion of the plug portion in longitudinal directions.

[0023] With this construction, the annular groove is engaged with the existing locking mechanism.

[0024] The plug portion is preferably cylindrical, the tip end of the plug portion being provided with an opening portion, and a valve for opening and closing the opening portion is preferably provided.

[0025] With this construction, the opening portion of the tip end of the plug portion is open and closed by the valve to open and close the fluid passage.

[0026] The plug portion is preferably provided with a valve for opening and closing an opening portion thereof, the valve being provided with a communication hole which establishes a fluid communication while being spaced from a valve seat of the plug portion, and the tip end of the valve being formed with an opening and closing protrusion for pushing a member, which is to be connected to the plug for fluid pipe connector, to separate the valve from the seat valve.

[0027] With this construction, the opening and closing protrusion of the tip end of the valve pushes the member, which is to be connected to the plug for fluid pipe connector, to separate the valve from the seat valve, and in this state, a fluid communication is established by the communication hole.

[0028] According to another aspect of the present invention, there is provided a plug for fluid pipe connector for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank or a processing unit, the plug comprising: a plug portion, the rear portion of which is fixed and from the front portion of which a liquid spouts out, the plug portion having a thread on the outer periphery thereof; a fixed plate portion which is formed by enlarging the end portion of a fluid pipe outwardly in circumferential directions in the form of a flange shape; a fixing portion which is formed with a thread groove in the inner periphery thereof and which is screwed to the plug portion for sandwiching the fixed plate portion between the fixing portion and an end portion of the plug portion to fix and support the fixed plate portion; and a cylindrical supporting portion which is integrally provided on the fixing portion for gently supporting thereon the fluid pipe.

[0029] With this construction, the fixing portion is screwed to the thread of the plug portion to fix the fixed plate portion of the end portion of the fluid pipe, so that it is possible to decrease the number of parts and the outside diameter of the plug for fluid pipe connector.

BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be understood more fully from the detailed description given herebelow and from the accompanying drawings of the preferred embodiments of the invention. However, the drawings are not intended to imply limitation of the invention to a specific embodiment, but are for explanation and understanding only.

[0031] In the drawings:

[0032]FIG. 1 is a front sectional view of the first preferred embodiment of a plug for fluid pipe connector according to the present invention;

[0033]FIG. 2 is a front view of a conventional plug for fluid pipe connector;

[0034]FIG. 3 is a front sectional view showing a female side connecting portion in the first preferred embodiment of the present invention;

[0035]FIG. 4 is a plan view showing the female side connecting portion in the first preferred embodiment of the present invention;

[0036]FIG. 5 is a left side view showing the female side connecting portion in the first preferred embodiment of the present invention;

[0037]FIG. 6 is a front sectional view showing a plug portion of the plug for fluid pipe connector in the first preferred embodiment of the present invention;

[0038]FIG. 7 is a front view showing a fluid pipe and a pipe supporting portion of the plug for fluid pipe connector in the first preferred embodiment of the present invention;

[0039]FIG. 8 is a front sectional view showing a fixing nut of the plug for fluid pipe connector in the first preferred embodiment of the present invention;

[0040]FIG. 9 is a side view showing the fixing nut of the plug for fluid pipe connector in the first preferred embodiment of the present invention;

[0041]FIG. 10 is a sectional view taken along line A-A of FIG. 1; and

[0042]FIG. 11 is a front sectional view of the second preferred embodiment of a plug for fluid pipe connector according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] Referring now to the accompanying drawings, the preferred embodiments of a plug for fluid pipe connector according to the present invention will be described below.

[0044] First Preferred Embodiment

[0045] Referring to FIGS. 1 and 3 through 10, the first preferred embodiment of a plug for fluid pipe connector according to the present invention will be described below.

[0046] A fluid pipe connector 11 is a member for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank, a processing unit or the like. The fluid pipe connector 11 mainly comprises a female side connecting portion 12, and a plug 13 for fluid pipe connector serving as a male side connecting portion.

[0047] As shown in FIGS. 3 through 5, the female side connecting portion 12 mainly comprises a female side plug portion 15 and a housing 16.

[0048] The female side plug portion 15 mainly comprises an inner pipe 18, a shower ring 19 and a valve 20.

[0049] The inner pipe 18 is a member for connecting an external piping 22 to the shower ring 19. The inner pipe 18 is mounted in a slider portion 42 which will be described later. The base end portion (the right side end portion in FIG. 4) of the inner pipe 18 is connected to the external piping 22, and the tip end portion thereof is connected to the shower ring 19. The external piping 22 is one of fluid pipes when the fluid pipes are connected to each other, or a piping on the side of a storage tank or a processing unit when a fluid pipe is connected to the storage tank or the processing unit. The end portion of the external piping 22 is provided with a piping side flange portion 24. This piping side flange portion 24 is clamped by a fixing flange portion 26 on the side of the inner pipe 18 and a presser plate 27 to be fixed by means of a bolt 28, so that the external piping 22 is connected to the inner pipe 18.

[0050] The shower ring 19 is a member forming a fitting portion for receiving the plug 13 for fluid pipe connector. The whole shower ring 19 is substantially cylindrical. The base end side of the shower ring 19 serves as a part of a fluid passage of the female connecting portion 12. On the central portion of the shower ring 19, a valve seat 30 of the valve 20 is formed. The tip end side of the shower ring 19 serves as a cylindrical fitting portion 31 into which the tip end portion of the plug 13 for fluid pipe connector is fitted. The inside shape of the cylindrical fitting portion 31 is the same shape as the tip end portion of the plug 13 for fluid pipe connector. On the inside surface of the cylindrical fitting portion 31, an O-ring 32 is mounted. The O-ring 32 is a member for sealing the tip end portion of the plug 13 for fluid pipe connector when the plug 13 for fluid pipe connector is fitted into the cylindrical fitting portion 31. The base end of the shower ring 19 is provided with a screw portion 19A. This screw portion 19A is screwed to the slider portion 42, so that the shower ring 19 is connected to the slider portion 42.

[0051] Moreover, a cleaning pipe 34 is connected to the cylindrical fitting portion 31 of the shower ring 19. This cleaning pipe 34 is a member for cleaning the portions of valves 20 and 62 of the female side connecting portion 12 and plug 13 for fluid pipe connector. That is, before the plug 13 for fluid pipe connector is inserted into the female side connecting portion 12 to be completely connected thereto, pure water or cleaning chemicals are jetted from the cleaning pipe 34 to the portions of the valves 20 and 62 of the female side connecting portion 12 and plug 13 for fluid pipe connector to clean the tip end portions of the female side connecting portion 12 and plug 13 for fluid pipe connector. After cleaning, pure water or the like is discharged from a drain pipe 35 which is provided in a cylinder portion 43 of the housing 16.

[0052] The valve 20 is a member for opening and closing the tip end of the fluid passage of the female side connecting portion 12. This valve 20 is a dish shape, and is mounted on the valve seat 30 of the shower ring 19 while being biased by a spring 37. On the contact portion of the valve 20 to the valve seat 30, an O-ring 38 is provided for seating a gap between the shower ring 19 and the valve seat 30. Inside of the valve 20 adjacent to the O-ring 38, a plurality of communication holes 39 are provided. While the valve 20 is spaced from the valve seat 30, the communication holes 39 allow the chemicals or the like to flow, so that a fluid communication is established between the female side connecting portion 12 and the plug 13 for fluid pipe connector. The tip end of the valve 20 is formed with an opening and closing protrusion 40. This opening and closing protrusion 40 is a member for contacting an opening and closing protrusion 76 of the plug 13 for fluid pipe connector, which will be described later. When the opening and closing protrusion 40 contacts the opening and closing protrusion 76 of the plug 13 for fluid pipe connector to push the valve 62, the valve 20 is pushed to leave the valve seat 30 to be open. The same action occurs in the plug 13 for fluid pipe connector, so that a fluid communication is established between the female connecting portion 12 and the plug 13 for fluid pipe connector.

[0053] The housing 16 is a member for supporting thereon the female side plug portion 15 and for supporting thereon the fitted plug 13 for fluid pipe connector. This housing 16 comprises the slider portion 42 and the cylinder portion 43.

[0054] The slider portion 42 is reciprocatingly inserted into the cylinder portion 43. On the slider portion 42, the inner pipe 18 and shower ring 19 of the female side plug portion 15 are integrally mounted. Thus, the inner pipe 18 and the shower ring 19 reciprocate in accordance with the reciprocating motion of the slider portion 42, so that the female side connecting portion 12 and the plug 13 for fluid pipe connector are completely connected to or disconnected from each other. Furthermore, the complete connection means that the valves 20 and 62 are open to establish fluid communications on the sides of the female side connecting portion 12 and plug 13 for fluid pipe connector.

[0055] The tip end of the slider portion 42 is formed with a piston portion 45. This piston portion 45 is capable of reciprocating in a movable space 46 in the cylinder portion 43, which will be described later.

[0056] The cylinder portion 43 is a member for reciprocatingly supporting thereon the slider portion 42 and the shower ring 19 and for directly supporting thereon and fixing the fitted plug 13 for fluid pipe connector. The outside diameter of the slider portion 42 is set to be equal to the outside diameter of the shower ring 19, and the inside diameter of the full length of the cylinder portion 43 is set to be equal to the outside diameter of the slider portion 42 and so forth. Thus, the slider portion 42 and so forth are capable of reciprocating in the cylinder portion 43. Furthermore, the inside diameter of the cylinder portion 43 is enlarged in the vicinity of the center thereof to form the movable space 46. The slider portion 42 and the piston portion 45 are inserted into the movable space 46 to be capable of reciprocating in lateral directions. To both end portions of the movable space 46, air pressure supply pipes 49 and 50 are connected. Air pressure is selectively supplied from the air pressure supply pipes 49 and 50 to both ends of the movable space 46 to be suitably adjusted on the right and left sides of the piston portion 45, so that the piston portion 45 is moved to right and left. By the movement of the piston portion 45, the female side connecting portion 12 is completely connected to or disconnected from the plug 13 for fluid pipe connector. Furthermore, an O-ring 47 is provided on the outer periphery of the piston portion 45 to seal a gap between the outer peripheral surface of the piston portion 45 and the inner peripheral surface of the movable space 46.

[0057] One end portion (the left end portion in FIG. 3) of the cylinder portion 43 is provided with a lock lever 52, a lock lever sensor 53, a plug sensor 54 and key bolts 55.

[0058] The lock lever 52 is a lock mechanism for fixing the plug 13 for fluid pipe connector to the female connecting portion 12. This lock lever 52 comprises a lever portion 56 which is to be held by an operator's hand to be rotated, and a substantially semi-circular engaging piece 57 which is rotated by the lever portion 56 for engaging or releasing an engaged surface 79 of the plug 13 for fluid pipe connector, which will be described later.

[0059] The lock lever sensor 53 is a sensor for detecting whether the plug 13 for fluid pipe connector has been fixed on the side of the female side connecting portion 12 by means of the lock lever 12. This lock lever sensor 53 comprises an optical sensor or the like for detecting the presence of the lever portion 56 of the lock lever 52 when the lever portion 56 is in a locked state (a state shown by imaginary lines in FIG. 5).

[0060] The plug sensor 54 is a sensor for detecting whether the plug 13 for fluid pipe connector has been mounted in the female side connecting portion 12. This plug sensor 54 comprises an optical sensor or the like for detecting the presence of the plug 13 for fluid pipe connector when the plug 13 for fluid pipe connector is mounted in the female side connecting portion 12.

[0061] The key bolt 55 is a bolt which is designed to be fitted into a long groove 83 of the plug 13 for fluid pipe connector, which will be described later, for allowing the plug 13 for fluid pipe connector to be inserted into the female side connecting portion 12. The key bolt 55 is provided for each of a plurality of bolt holes. The mounting positions and number of the key bolts 55 are suitably set in accordance with the kind of the chemicals or the like. Thus, the plug 13 for fluid pipe connector can not be inserted into the female side connecting portion 12 unless the key bolt 55 is aligned with the long groove 83, so that erroneous connection is prevented.

[0062] The plug 13 for fluid pipe connector is a member which is mounted on the tip end portion of a fluid pipe 60 to be fitted into the female side connecting portion 12 for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank, a processing unit or the like. As shown in FIG. 1, this plug 13 for fluid pipe connector 13 comprises a plug portion 61, a valve 62, a pipe supporting portion 63, a fixing nut 64 and a locking nut 65.

[0063] The plug portion 61 is a member which is inserted directly into the shower ring 19 of the female side connecting portion 12 for connecting the plug 13 for fluid pipe connector to the female side connecting portion 12. As shown in FIGS. 1 and 6, this plug portion 61 is substantially cylindrical, and a valve seat 67 of the valve 62 is formed in the tip opening portion thereof. In the outer periphery of the central portion of the plug portion 61 in longitudinal directions (lateral directions in the figure), there is formed an annular groove 68 which is engaged with the existing locking mechanism to be fixed. On the base end portion of the plug portion 61, an enlarged diameter portion 69 for engaging the fixing nut 64 is formed. On the end face (the right end face in the figure) 70 of the enlarged diameter portion 69, an O-ring 71 for sealing a fluid passage is provided.

[0064] The valve 62 is a member for opening and closing the tip opening portion of the plug 61. This valve 62 is a dish shape, and is mounted on the valve seat 67 of the plug portion 61 while being biased by means of a spring 73. On the contact portion of the valve 62 to the valve seat 67, an O-ring 74 is provided for seating a gap between the valve 62 and the valve seat 67. Inside of the O-ring 74 of the valve 62, a plurality of communication holes 75 are provided. While the valve 62 is spaced from the valve seat 67, the communication holes 75 allow the chemicals or the like to flow, so that a fluid communication is established between the female side connecting portion 12 and the plug 13 for fluid pipe connector. The tip end of the valve 62 is formed with an opening and closing protrusion 40 for pushing the opening and closing protrusion 40 of the valve 20 on the side of the female side connecting portion 12 to cause the valve 62 to leave the valve seat 67. Furthermore, reference number 77 is a stopper for supporting thereon the base end portion of the spring 73.

[0065] The pipe supporting portion 63 is a member for fixing and supporting thereon the tip end portion of the fluid pipe 60 and for supporting it by a predetermined distance (e.g., about 10 cm) from the tip end portion. As shown in FIGS. 1 and 7, this pipe supporting portion 63 comprises a fixing portion 78, an engaged surface 79, and a cylindrical supporting portion 80.

[0066] The fixing portion 78 is formed so as to have an outside diameter corresponding to the inside diameter of the fixing nut 64 and the locking nut 65. In the outer periphery of the fixing portion 78, a thread is formed. The fixing nut 64 and the locking nut 65 are designed to be screwed to the thread of the fixing portion 78. The tip end (the left end in the figure) of the fixing portion 78 is formed with a fixing face 82. This fixing face 82 is formed so as to decrease the diameter of the tip end portion of the fixing portion 78, and is designed to sandwich the end portion of the fluid pipe 60 between the plug portion 61 and the end face 70 to fix the end portion.

[0067] The engaged surface 79 is a portion which is engaged with the engaging piece 57 of the lock lever 52 for fixing the plug 13 for fluid pipe connector to the female side connecting portion 12. This engaged surface 79 is formed between the large diameter fixing portion 78 and the small diameter cylindrical supporting portion 80.

[0068] The cylindrical supporting portion 80 is a member for supporting the fluid pipe 60. Since the tip end portion of the fluid pipe 60 is only sandwiched between the end face 70 of the plug portion 61 and the fixing face 82 of the fixing portion 78 to be fixed, it is easily loosened when the fluid pipe 60 bends due to its weight. In order to prevent this, the cylindrical supporting portion 80 supports thereon a portion of the fluid pipe 60 having a length of about 10 cm from the tip end portion thereof. If the fluid pipe 60 is supported on the cylindrical supporting portion 80, the tip end portion of the fluid pipe 60 hardly bends, so that the portion fixed by the end face 70 and the fixing face 82 is prevented from being loosened. This cylindrical supporting portion 80 comprises a cylinder having an inside diameter which is slightly larger than the outside diameter of the fluid pipe 60. Thus, a play is allowed between the cylindrical supporting portion 80 and the fluid pipe 60. By this play, the fluid pipe 60 is gently supported, so that the fluid pipe 60 does not bent at an acute angle. Moreover, the cylindrical supporting portion 80 serves as a holder which is to be held by the operator's hand.

[0069] The fixing nut 64 is a member for fixing the plug portion 61 together with the pipe supporting portion 63. This fixing nut 64 is formed as shown in FIGS. 1 and 8 through 10. In the inside surface of the fixing nut 64 on the side of the base end (the right side in the figure), a thread groove 64A for engaging the thread of the fixing portion 78 is formed. The inside diameter of the fixing nut 64 on the tip end side is set to be substantially equal to the outside diameter of the enlarged diameter portion 69 of the plug portion 61. The tip end portion of the fixing nut 64 is formed by decreasing the diameter thereof, and is designed to surround and support the enlarged diameter portion 69. Thus, if the base end side of the fixing nut 64 is screwed to the thread of the fixing portion 78 while the tip end portion of the fixing nut 64 surrounds and supports the enlarged diameter portion 69, the plug portion 61 is fixed to the pipe supporting portion 63. In the outer peripheral surface of the fixing nut 64, long grooves 83 are formed. The long grooves 83 extend in longitudinal directions (lateral directions in FIG. 1) of the fixing nut 64. The number and positions of the long grooves 83 are set in accordance with the kind of the chemicals or the like, so that erroneous connection is prevented. Furthermore, reference number 64B denotes a flatted portion for clamping the fixing nut 64.

[0070] The locking nut 65 is screwed to the thread of the fixing portion 78 to pressingly contact the fixing nut 64 to prevent the fixing nut 64 from being rotated and loosened.

[0071] As shown in FIGS. 1 and 7, the fluid pipe 60 comprises an inner tube 84 of PFA, an intermediate tube 85 (see FIG. 11) of a synthetic resin, and an outer tube 86 formed of a net material of stainless steel. The tip end of the fluid pipe 60 is formed with a fixed plate portion 87. This fixed plate portion 87 is mounted on the tip end of the fluid pipe 60, and is formed so as to be extended outwardly in circumferential directions in the form of a flange shape. From this fixed plate portion 87, the intermediate tube 85 and the outer tube 86 are peeled off. Thus, the inner tube 84 is formed so as to be extended outwardly along the flange-shaped fixed plate portion 87 in the form of a flange shape. The fixed plate portion 87 and the inner tube 84 are sandwiched between the plug portion 61 and the pipe supporting portion 63 to be fixed.

[0072] The base end of the fluid pipe 60 is formed with a fixing flange portion 89. In this fixing flange portion 89, a plurality of bolt holes 90 are formed. The fixing flange portion 89 is connected to a fixing flange portion (not shown), which is formed on a piping on the side of a storage tank or one of various processing units, to be fixed by bolts.

[0073] With the above described construction, the operation of the fluid pipe connector 11 is as follows.

[0074] First, the plug 13 for fluid pipe connector is inserted into the cylinder 43 of the female side connecting portion 12, and the lever portion 56 of the lock lever 52 is rotated to a locking position. Thus, the engaging piece 57 is rotated to be engaged with the engaged surface 79 of the plug 13 for fluid pipe connector. In this state, the plug 13 for fluid pipe connector is fixed to the side of the female side connecting portion 12. Furthermore, when the plug 13 for fluid pipe connector is inserted into the female side connecting portion 12, the long groove 83 is aligned with the key bolt 55. If these are not aligned with each other, the plug 13 for fluid pipe connector can not be connected to the female side connecting portion 12. Finally, the connection of the plug 13 for fluid pipe connector is erroneously carried out.

[0075] In the female connecting portion 12, air pressure is supplied from the air pressure supply pipe 5 into the movable space 46, so that the shower ring 19, together with the slider portion 42, is moved toward the base end as shown by the solid line in FIG. 3. Thus, a space is formed between the valve 20 on the side of the female side connecting portion 12 and the valve 62 on the side of the plug 13 for fluid pipe connector.

[0076] Then, pure water is jetted from the cleaning pipe 34 to clean the plug 13 for fluid pipe connector and the respective valves 20 and 62 of the female side connecting portion 12. Furthermore, the lock lever sensor 53 is designed to detect the lock lever 52. When the plug sensor 54 has not detected the plug 13 for fluid pipe connector, pure water or the like is prevented from being jetted from the cleaning pipe 34. That is, the lock lever sensor 53 is designed to detect the lock lever 52, and pure water is jetted only when the plug sensor 54 detects the plug 13 for fluid pipe connector.

[0077] Then, air pressure is supplied from the air pressure supply pipe 49 into the movable space 46, so that the shower ring 19 is moved to a position shown by the imaginary line in FIG. 3. Thus, the opening and closing protrusion 76 of the valve 62 on the side of the plug 13 for fluid pipe connector contacts and pushes the opening and closing protrusion 40 of the valve 20 on the side of the female side connecting portion 12, so that the tip end portion is open. Thus, a fluid communication is established between the plug 13 for fluid pipe connector and the female side connecting portion 12, so that a fluid flows therethrough to be supplied to the storage tank or processing unit, or to be collected.

[0078] At this time, the fluid pipe 60 is gently supported on the cylindrical supporting portion 80 of the pipe supporting portion 63. For that reason, even if the operator holds the cylindrical supporting portion 80 to take the fluid pipe 60 around during connection operation or even if the fluid pipe 60 bends due to the weight of the fluid pipe 60 itself or the weight of chemicals passing through the fluid pipe 60 after connection, the portion of the fixed plate portion 87 hardly bends, and the end face 70 of the plug portion 61 is fixed to the fixing face 82 of the fixing portion 78.

[0079] When the plug 13 for fluid pipe connector is detached from the female side connecting portion 12, air pressure is first supplied from the air pressure supply pipe 50 into the movable space 46 to move the slider portion 42 to block the fluid communication between the female side connecting portion 12 and the plug 13 for fluid pipe connector. Then, after pure water or the like is jetted from the cleaning pipe 34 to clean liquid adhering to the valve 62 and so forth, the lever portion 56 of the lock lever 52 is rotated to unlock to pull the plug 13 for fluid pipe connector out of the female side connecting portion 12.

[0080] As described above, since the plug portion 61 and the fixing portion 78 are fixed so as to be covered with the fixing nut 64, the plug 13 for fluid pipe connector can be miniaturized and easily handled.

[0081] In addition, since the fluid pipe 60 is gently supported on the cylindrical supporting portion 80 of the pipe supporting portion 63, the fluid pipe 60 does not bend at an acute angle to be broken.

[0082] Moreover, since the fluid pipe 60 is supported on the cylindrical supporting portion 80 to prevent the fluid pipe 60 from greatly bending at the portion of the fixed plate portion 87 sandwiched between the plug portion 61 and the fixing portion 78, it is possible to surely prevent this portion from bending.

[0083] Since the pipe supporting portion 63 of the plug 13 for fluid pipe connector is provided with the engaged surface 79, it is possible to surely fix the plug 13 for fluid pipe connector to the female side connecting portion 12.

[0084] Since the valve 62 is provided on the tip end portion of the plug portion 61, the plug portion 61 is not open unless the valve 62 contacts and pushes the valve 20 of the female side connecting portion 12 which is to be connected thereto, so that safety in handling is improved.

[0085] In addition, since the long groove 83 is formed in the outer peripheral surface of the fixing nut 64, the plug 13 for fluid pipe connector can not be inserted into the female side connecting portion 12 unless the long groove 83 is aligned with the key bolt 55 of the female side connecting portion 12 which is to be connected to the plug 13 for fluid pipe connector. Therefore, this plug 13 for fluid pipe connector is not erroneously mounted, so that safety in handling is improved.

[0086] Second Preferred Embodiment

[0087] Referring to FIG. 11, the second preferred embodiment of the present invention will be described below. A plug for fluid pipe connector in this preferred embodiment is characterized in that the fixing nut 64 in the above described first preferred embodiment is not provided and a thread groove is formed directly in the pipe supporting portion 63 to decrease the number of parts. Since other constructions are substantially the same as those of the plug 13 for fluid pipe connector in the above described first preferred embodiment, the same reference numbers are given to the same elements to omit the descriptions thereof.

[0088] In this preferred embodiment, a thread is formed directly on the outer periphery of the base end portion of a plug portion 101. The base end face of the plug portion 101 serves as an end face 102 for clamping and fixing a fixed plate portion 87.

[0089] A pipe supporting portion 103 comprises a fixing portion 104, an engaged surface 105 and a cylindrical supporting portion 106. A thread groove is formed in the inside surface of the fixing portion 104. The fixing portion 104 is screwed directly to the base end of the plug portion 101 to be fixed thereto. Moreover, the locking nut 108 is clamped to prevent the fixing portion 104 from being loosened.

[0090] The engaged surface 105 and the cylindrical supporting portion 106 have the same constructions of the engaged face 79 and the cylindrical supporting portion 80 in the above described first preferred embodiment.

[0091] A fixing face 107 for fixing the fixed plate portion 87 to the end face of the plug 101 is formed on the reverse surface of the engaged surface 105.

[0092] The plug for fluid pipe connector with the above described construction is also connected to the female side connecting portion 12 by the same function as the above described first preferred embodiment, so that the same effects are provided.

[0093] As described above in detail, according to the present invention, the following effects are provided.

[0094] Since the plug portion and the fixing portion are covered with the fixing nut, the plug for fluid pipe connector can be small and light. As a result, it is easy to handle the plug for fluid pipe connector.

[0095] In addition, since the fluid pipe is gently supported on the cylindrical supporting portion of the pipe supporting portion, it is possible to prevent the fluid pipe from bending at an acute angle to be broken.

[0096] Moreover, since the fluid pipe is supported on the cylindrical supporting portion to prevent the fluid pipe from greatly bending at the portion of the fixed plate portion which is sandwiched between the plug portion and the fixing portion, it is possible to surely prevent this portion from bending.

[0097] Since the plug for fluid pipe connector is provided with the engaged surface for the locking mechanism, the locking mechanism is engaged with the engaged surface, so that it is possible to surely fix the plug for fluid pipe connector to the female side connecting portion.

[0098] Since the valve is provided on the tip end portion of the plug portion, the plug portion is not open unless this valve contacts and pushes the valve of the female side connecting portion which is to be connected thereto, so that safety in handling is improved.

[0099] In addition, since the long groove is formed in the outer peripheral surface of the fixing nut, the plug for fluid pipe connector can not be inserted into the female side connecting portion unless the long groove is aligned with the female side connecting portion which is to be connected to the plug for fluid pipe connector. Therefore, this plug for fluid pipe connector is not erroneously mounted, so that safety in handling is improved.

[0100] While the present invention has been disclosed in terms of the preferred embodiment in order to facilitate better understanding thereof, it should be appreciated that the invention can be embodied in various ways without departing from the principle of the invention. Therefore, the invention should be understood to include all possible embodiments and modification to the shown embodiments which can be embodied without departing from the principle of the invention as set forth in the appended claims. 

What is claimed is:
 1. A plug for fluid pipe connector for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank or a processing unit, said plug for fluid pipe connector comprising: a plug portion, the rear portion of which is fixed and from the front portion of which a liquid spouts out; a fixed plate portion which is formed by enlarging the end portion of a fluid pipe outwardly in circumferential directions in the form of a flange shape; a fixing portion for sandwiching said fixed plate portion between said fixing portion and an end portion of said plug portion to fix and support said fixed plate portion; a cylindrical supporting portion which is integrally provided on said fixing portion for gently supporting thereon said fluid pipe; and a fixing nut for covering and fixing said plug portion and said fixing portion.
 2. A plug for fluid pipe connector as set forth in claim 1, which is provided with a portion having a difference in level in the outer periphery thereof to provide an engaged surface for a locking mechanism.
 3. A plug for liquid pipe connector as set forth in claim 1, which further comprises a valve provided on the tip end of said plug portion, said valve being establishing a fluid communication when said valve is pushed into a member, which is to be fixed, to be open.
 4. A plug for liquid pipe connector as set forth in claim 2, which further comprises a valve provided on the tip end of said plug portion, said valve being establishing a fluid communication when said valve is pushed into a member, which is to be fixed, to be open.
 5. A plug for fluid pipe connector as set forth in claim 1, which further comprises a long groove for preventing said plug from being erroneously mounted, said long groove being formed in the outer peripheral surface of said fixing nut.
 6. A plug for fluid pipe connector as set forth in claim 1, which further comprises a long groove for preventing said plug from being erroneously mounted, said long groove being formed in the outer peripheral surface of said fixing nut.
 7. A plug for fluid pipe connector as set forth in claim 1, which further comprises a long groove for preventing said plug from being erroneously mounted, said long groove being formed in the outer peripheral surface of said fixing nut.
 8. A plug for fluid pipe connector for connecting fluid pipes to each other or for connecting a fluid pipe to a storage tank or a processing unit, said plug for fluid pipe connector comprising: a plug portion, the rear portion of which is fixed and from the front portion of which a liquid spouts out, said plug portion having a thread on the outer periphery thereof; a fixed plate portion which is formed by enlarging the end portion of a fluid pipe outwardly in circumferential directions in the form of a flange shape; a fixing portion which is formed with a thread groove in the inner periphery thereof and which is screwed to said plug portion for sandwiching said fixed plate portion between said fixing portion and an end portion of said plug portion to fix and support said fixed plate portion; and a cylindrical supporting portion which is integrally provided on said fixing portion for gently supporting thereon said fluid pipe.
 9. A plug for fluid pipe connector as set forth in claim 1, wherein an enlarged diameter portion to be engaged with said fixing nut is formed on the base end of said plug portion.
 10. A plug for fluid pipe connector as set forth in claim 9, wherein an O-ring for sealing a fluid passage is provided on an end face of said enlarged diameter portion.
 11. A plug for fluid pipe connector as set forth in claim 1, which further comprises a locking nut which pressingly contacts said fixing nut for preventing said fixing nut from being rotated to be loosened.
 12. A plug for fluid pipe connector as set forth in claim 1, wherein an annular groove, which is fitted into a locking mechanism to be fixed, is formed in the outer periphery of the central portion of said plug portion in longitudinal directions.
 13. A plug for fluid pipe connector as set forth in claim 1, wherein said plug portion is cylindrical, the tip end of said plug portion being provided with an opening portion, and a valve for opening and closing said opening portion is provided.
 14. A plug for fluid pipe connector as set forth in claim 1, wherein said plug portion is provided with a valve for opening and closing an opening portion thereof, said valve being provided with a communication hole which establishes a fluid communication while being spaced from a valve seat of said plug portion, and the tip end of said valve being formed with an opening and closing protrusion for pushing a member, which is to be connected to said plug for fluid pipe connector, to separate said valve from said seat valve. 